Assembled block copolymer stabilized high internal phase emulsion hydrogels for enhancing oil safety

Accidental spills and subsequent fires during oil storage and transportation periods cause serious damage to environments. Herein, we present a novel route to enhance oil safety by transforming oils into high internal phase emulsion (HIPE) hydrogels. These HIPE hydrogels are stabilized by solvent- or pH-driven assembled block copolymer (BCP), namely poly(4-vinylpyridine)-block-poly(ethylene glycol)-block-poly(4-vinylpyridine) (4VPm-EGn-4VPm). The assembled BCP shows high efficiency to stabilize HIPE hydrogels with a low concentration of 1.0 (w/v) % relative to the continuous aqueous phase. The volume fraction of the dispersed organic phase can be as high as 89% with a variety of oils, including toluene, xylene, blended vegetable oil, canola oil, gasoline, diesel, and engine oil. These smelly and flammable liquids were formed into HIPE hydrogels and thus their safety was enhanced. As the assembly is pH sensitive, oils trapped in the HIPE hydrogels can be released by simply tuning pH values of the continuous aqueous phase. The aqueous phase containing BCP can be reused to stabilize HIPE hydrogels after naturalization. These assembled BCP stabilized HIPE hydrogels offer a novel and safe approach to preserve and transport these smelly and flammable liquid oils, avoiding environmental damage.

Nano titanium dioxide on wool keratin as UV absorber stabilized by butane tetra carboxylic acid (BTCA): a statistical prospect

Photo yellowing of wool is one of the most important problems which have negative impacts on various aspects of wool prompting scientists to find a solution over the past decades. In this research the protective features of nano-titanium dioxide particles against UV on wool fabric were discussed and the color variations of wool samples after UV irradiation were measured and reported. It was shown that nano TiO2 is a suitable UV absorber and its effect depends on the concentration. Also, it was assumed that butane tetracarboxylic acid plays a prominent role as a cross-linking agent to stabilize the nano-titanium dioxide as well as a polyanion to maintain negative charges on the wool surface for higher nano particles absorption. Also the variables conditions were optimized using response surface methodology (RSM).

The influence of titania-zirconia-zirconium titanate nanotube characteristics on osteoblast cell adhesion

Studies of biomaterial surfaces and their influence on cell behavior provide insights concerning the design of surface physicochemical and topography properties of implant materials. Fabrication of biocompatible metal oxide nanotubes on metallic biomaterials, especially titanium alloys such as Ti50Zr via anodization, alters the surface chemistry as well as surface topography of the alloy. In this study, four groups of TiO2-ZrO2-ZrTiO4 nanotubes that exhibit diverse nanoscale dimensional characteristics (i.e. inner diameter Di, outer diameter Do and wall thicknesses Wt) were fabricated via anodization. The nanotubes were annealed and characterized using scanning electron microscopy and 3-D profilometry. The potential applied during anodization influenced the oxidation rate of titanium and zirconium, thereby resulting in different nanoscale characteristics for the nanotubes. The different oxidation and dissolution rates both led to changes in the surface roughness parameters. The in vitro cell response to the nanotubes with different nanoscale dimensional characteristics was assessed using osteoblast cells (SaOS2). The results of the MTS assay indicated that the nanotubes with inner diameter (Di)≈40nm exhibited the highest percentage of cell adhesion of 41.0%. This result can be compared to (i) 25.9% cell adhesion at Di≈59nm, (ii) 33.1% at Di≈64nm, and (iii) 33.5% at Di≈82nm. The nanotubes with Di≈59nm exhibited the greatest roughness parameter of Sa (mean roughness), leading to the lowest ability to interlock with SaOS2 cells.

Polymer organogels stabilized HIPE organogels and applications in oil fields

This research focuses on polymer stabilized high internal phase emulsions for oil spill recovery and oil safety.